Piawofokte



T. GILBERT. PIANOFORTE ACTION.

No. 8.389. Patented Sept. 30; 1851.

UNITED STATES PATENT OFFICE.

T. GILBERT, OF BOSTON, MASSACHUSETTS.

PIANOFORTE.

Specification of Letters Patent No. 8,389, dated September 30, 1851.

To all whom it may concern.

Be it known that I, TIMOTHY GILBERT, of Boston, in the county of Suffolk and State of Massachusetts, have invented a new and useful or Improved Pianoforte-Action; and I do hereby declare that the same is fully described and represented in the following specification and accompanying drawings, letters, figures, and references thereof.

Of the said drawings Figure 1, denotes a side view of my improvements as embodied in an action for an upright piano forte. Fig. 2, shows a side view of a horizontal piano forte action, as will be hereinafter described.

In the said drawings A, represents the key lever, made to operate in the usual manner.

B is the hammer; O, the string against which the hammer strikes.

D, is the tail block of the hammer, which turns upon a pin or fulcrum, E, supported by a bearing piece F, that extends from a rail G. The hammer head is shown at a, while its stem is seen at b.

H, is the fly jack or escapement which in Fig. 1, is shown, as hinged to a horizontal lever I, that turns up andfdown upon a ful crum or pin 0, at one end and is raised and lowered by the key lever, acting through a bar K, that rests upon the rear end of the said key lever, and extends upward underneath and abuts against the lever I, as seen in Fig. 1. The back catch L, in Fig. 1, extends upward from the lever I, and works in connection with an arm M, that extends outward from a projection LT, extending either from the tail block D, or the stem 5, of the hammer, as seen in the drawings. The said tail block of the hammer is represented as carrying the small projection 0, against which the top of the fly operates, for the purpose of elevating the hammer or throw ing it against the string, the fly being thrown off from the part 0, by the action of a regulating button P, which is fixed upon a screw Q, that extends through the tail block as, seen in the drawings, such being common to other piano forte actions. For the purpose of damping the sound of the blow of such button against the fly, a piece of damper cloth R, or other suitable material is suspended from the tail block, and made to hang between the fly, and the button as seen in the drawings.

Another regulating screw S, is extended through the arm or projection N, and car rise a button T, on its inner end, as seen in the drawings, the said button being made to operate against that side of the fly, which is oppositeto the side against which the button P, acts. A piece of damper cloth U, is attached to the projection N, and made to hang down between the button T, and the fly H, as seen in the drawings.

The damper for the string is shown (at V in Fig. 1,) as attached directly to the tail block of the'hanimer, or a projection therefrom. The retractive spring of the fly is seen at IV, it being made to operate in the usual way.

The difference between what is termed the horizontal or square piano, and the upright piano, whether a full upright boudoir or piccolo is well known and understood among piano forte makers, the horizontal piano forte having its strings arranged in or about in a horizontal plane, while the upright boudoir or piccolo has its strings arranged in an upright vertical or nearly vertical plane.

The action of the retractive power of the spring IV, is not always suflicient or quick enough for very rapid and successive blows of the hammer against the string. This may arise from various causes. In order to insure the return of the fly into the notch of the tail block, immediately after the blow of the hammer, on the string, and thereby secure a full blow of the hammer, or a succession of blows in a very rapid and quick manner, and with the least possible liability of failure during such repetition of the blows, I employ the projection N, button T, and screw S, applied to the stem of the hammer, on its tail block, substantially in the manner, and made to operate in conjunction with the other button P, and upon the fly, as described, such button T, being made to act on the fly by a blow or percussion such as renders it sure to pass into the notch of the tail block. By such improvement while the escapement of the fly is secured, its return under the projection 0, or into what is usually termed the notch of the tail block is also effectually obtained and a more rapid and effective action of the hammer rendered certain.

In Fig. 2, is shown the application of the return screw S, and its button T, to the hammer of the horizontal, action.

By the arrangement of the damper V, directly upon the tail block, of the hammer or a projection extending downward thereand button T, or equivalent contrivance or oontrivances with the hammer, and fly, and its retractive spring, so as to operate in manner and in connection with the same, and other parts, substantially as herein de scribed.

In testimony whereof I have hereto set my signature this nineteenth day of March TIMOTHY GILBERT. Vitnesses R. H. EDDY,

BENJAMIN EDDY. 

